Thursday, April 29, 2010

How the Nittany Lions are using the science of acoustics to help crank up home field crowd noise.

Loud stadiums help win games, and Penn State's Beaver Stadium is one of the loudest in college football. When its crowd roars at a visiting quarterback, his calls can only be heard from a foot and a half away.

Next season, the university's athletic department will put into play a new strategy to make its field even louder thanks to a team of acoustic scientists. The goal is to send a deafening wall of sound at the opposing team's offensive line.

"We're not going to let visiting teams get comfortable, and if you can't get comfortable, you're probably not going to perform as well," said Guido D'Elia, director for communications and branding for Penn State football.Working with D'Elia in 2007-08, Penn State graduate student Andrew Barnard recorded crowd noise during three home games. Using 11 sound meters strategically placed around the field, he compared volume levels when each team had the ball.

When the Penn State's Nittany Lions were on the offense the noise levels inside 107,282-seat Beaver Stadium reached 75 decibels on the field. That's about as loud as a car radio playing at a reasonable volume.

But the noise skyrocketed to 110 decibels -- 50 times as loud -- when visiting teams were on offense, drowning out the calls of the quarterback and making last-minute adjustments at the line of scrimmage very difficult.

"For the visiting quarterback that would be like trying to have a conversation while standing next to a giant speaker at a rock concert," said Barnard.

The numbers support a 2007 ESPN survey in which coaches gave Penn State the highest marks of any stadium for noise -- higher than Louisiana State University's Tiger Stadium, where cheers after a 1988 touchdown were picked up by seismographs across campus set up to measure earthquakes.

"Everyone wants to say that they have the loudest fans, everyone wants that badge of honor," said Barnard. "Any big stadium is going to claim that they're the loudest, but Penn State is only one with data to back that up."

As an added advantage, the Nittany Lions play Barnard's recordings during practice to prepare for the noise they will face at other stadiums. They are confident that they will not hear anything worse on the road than what their own fans can produce.

Maximizing Call Interference

Penn State used acoustic science not just to earn bragging rights, but also to look for ways to increase the home field advantage.

"We were curious about which sections were loudest and reach the field best," said D'Elia.

Barnard presented his data during an Acoustical Society of America meeting in Baltimore. His measurements showed that, as expected, the student section -- which stretches from the middle of the southern end zone to the 30-yard line on one side -- made the most sound of any part of the stadium.

"Our students have really found their voice in the past six or seven years," said D'Elia. "We used to be the quietest stadium over 100,000 [seats]."

Barnard is confident that moving the students to different seats could make them sound even louder.

When the stadium was empty, he searched for the best spots for an audible assault by carrying a noisy speaker around to 45 different seats and measuring how loud it sounded on the field. A computer model crunched this data to fill in the rest of the stadium.

For seats on the sidelines, closer was better. Students sitting in the highest rows contributed very little to the overall sound.

But the situation was reversed behind the end zone. Higher seats could be heard better than field-level seats because of a trick of the stadium's architecture, said Barnard.

Stadiums with a steeper slope, like Oregon State University's Reser Stadium, are generally thought to hold sound in better than Penn State's stadium. But according to Barnard's data, Beaver Stadium's upper deck -- which juts out toward the field at the end zones -- may act like a megaphone that catches and amplifies the sound in the higher seats of the lower levels.

To take advantage of this acoustic effect, Penn State plans to move the 20,000 seats in its student section squarely into the southern end zone when the entire stadium is reseated for the 2011 season. Barnard's computer model predicts that this relocation will quiet the east side of field slightly but increase the sound on the west side by almost 50 percent -- cutting the range of a quarterback's voice by another six inches and potentially causing more fall starts and penalty opportunities.

"We will own that end zone," said D'Elia. "The students' voices will have an unobstructed view of the entire field, and when another team is down in that end, we'll be able to maintain that home field advantage."

Wednesday, April 28, 2010

So a while back, fellow buzz-blogger uncountable and myself were having a discussion about our favorite reality TV shows. I was deep in the heart of season 7 of Project Runway and uncountable was fixated on Ru Paul's Drag Race. We somehow came up with the idea to challenge each other to find a physics angle for each show and write a post about it. No alcohol was involved, so I guess that means we have to take the challenge seriously now. I was reminded of this challenge because of Kendra's post yesterday where an anonymous commenter actually mentioned Drag Race and suggested we go to the website and turn our favorite physicists into drag queens (it has been said and it cannot be unsaid!). Either that commenter was actually uncountable (who must be too lazy to sign in) or this is further proof that us science nerds do enjoy things non-science related from time to time (or we are all secretly hooked on fashion-related-reality-TV?).

Anyway, I am going to go for the easy-out here and actually make reference to Diana Eng who was on the show in season 2. So far as I can tell she is one of the adorably awkward queens of the "fashion nerds," or folks who combine science and technology with fashion. She has a book out about integrating technology and fasion called Fashion Geek: Clothes, Accessories and Tech, and it has this description on her website:

In Fashion Geek, Diana pioneers an emerging generation of tech savvy women crafters (or would-be crafters) who demand stylish yet practical designs that are electronically charged. Now you can take simple, girly items such as a hoodie or scarf and transform them into must-have techno-accessories through approachable, step-by-step directions. Full-color photos make it easy to see how every project comes to life.

She auditioned for Project Runway with a hoodie she designed that had a camera and a heart rate monitor built in. The two are connected, and assuming that your heart rate goes up when you see something you like, the camera (positioned in the hood, so you have to have it up on your head for this to work) takes a photo when you see something gets you excited.Eng left the Project Runway competition mid-way through but apparently she has been insanely busy ever since because her blog is just loaded with cool content. In addition, she manages a project called Fairy Tale Fashion, where in readers actually submit designs and ideas for innovative fashion and Eng helps to make them a reality. She featured a video explaining to viewers the science of biomimetic deployable structures, or geometric structures which change shape easily (like an umbrella). You also see this in leaves and flowers that open and close. Eng translates these origami-like folded patterns into a scarf, a hooded poncho and the shoulders of a blouse. Her first fashion show for Fairy Tale Fashion puts them on display, along with some awesome LED dresses.

But my absolute favorite story from her blog is her experience on PBS's SciGirls, which is a show, you guessed it, about girls doing science. Eng worked with some youngsters to make a super hero prince dress fairy tale princess dress for the Fairy Tale Fashion line. I love that these girls both loved the science and were totally girly. They're too young to worry about that being a good or a bad thing in a male dominated field. They just do what they like and that's that. From Eng's blog:

The girls designed the super hero prince dress and I showed them how to make it. The dress had an EL wire cape controlled by an accelerometer so that the cape lit up in reaction to motion. And the skirt inflated to create a billowing cloud effect which every flying superhero princess needs.

The girls programmed an Arduino microcontroller to make conductive thread embroidered LEDs sparkle on lace. The girls really liked sparkly things. When I was showing them how to program the Arduino to make the LEDs sparkle, they practically pushed me out of the way so that they could program the sparkles themselves. I didn’t even finish explaining how to write the program. The girls just took over.

In between takes, Ariella, Hallie, and Sophia made up a song and dance for everything, the ironing dance, the LED song. It would be interesting to see little girls take over the electronics world with sparkle programs and soldering songs.

This just makes my freaking day - thinking about little girls singing programming songs while building an LED dress. You can watch the episode here.

So I don't know if this is cheating because the post was barely about Project Runway, but it was about fashion. One way or another the ball is in your court now, uncountable! May the best blog win! (there is no winner, this is all in good fun/doing our jobs).

Monday, April 26, 2010

As a birthday present, maybe. As a free gift at the cosmetic counter, maybe. But as a give-away at a gathering of National Science Foundation funded projects? That caught me by surprise.

The gloss was met with mixed reactions. Some of the female scientists thought it was offensive, some thought it was cool, and some, like me, thought a little of both. The give-away, according to the giver, was meant to send the message that women don't have to change (meaning become more man-like) to succeed in a science research career.

With the intention of treading the lighter side, I thought I'd look into the physics of lipstick instead of treating you all to my not-quite-developed thoughts about women in physics. To my surprise, I came across Institute of Physics, lipstick, and beer all in the same sentence.

Apparently, the Institute of Physics (IOP) sponsored a 4-week initiative last fall aimed at igniting discussions about the physics of food and drink. One of the questions was, seriously, How does wearing lipstick affect your beer drinking? (Don't worry, it's multiple choice)A. the fats in lipstick destroy the foamy headB. lipstick makes the glass slippy and harder to holdC. the perfume in lipstick makes the beer taste sweeter

Personal experience (not my vast knowledge of physics) led me to believe that it must be A, because B and C don't make much sense. Unless you have on the really tasty lip stuff, and that would wear off before the end of the first drink.

In this case, reality seems to match physics.

The physics (or chemistry), goes like this. Foam is made from CO2 gas bubbles that form as the beer is poured. The bubbles are enclosed in a protein skin, which increases their stability. Fat, in lipstick, nuts, or whatever, essentially pokes holes in the proteins and deflates the bubbles. This is according to my very limited understanding, and I will point you toward the very excellently titled, The Relative Significance of Physics and Chemistry for Beer Foam Excellence: Theory and Practice for more information on beer foam formation.

Other give-aways at this event included a tornado in a jar, a robotics patch, the usual pens and stickers, and I can't even remember what else. By far the most memorable was the lip gloss. Which makes me think that no matter what message it is meant to send to the larger science community, it is definitely sending a "notice me" message.

What do you think? Would you rather get lip gloss or a luggage tag touting a ULR for an NSF funded project? The project, by the way, is an initiative by Ohio State University called Project CEOS (Comprehensive Equity at Ohio State) to train and support women interested in patenting their work, among other things.

"Every faculty member wants her research to make a difference, yet most view the end product of their work as the refereed publication or conference presentation. This workshop series, cosponsored with the Office of Academic Affairs and the Office of Research, will introduce faculty to a different route to provide impact, by partnering with commercial entities," reads a description on the website.

One motivation for the project is that women are much less likely than their male counterparts to apply for patents, hence the workshops. The ongoing question remains, when do women have to change to fit the environment, and when does the environment need to change?

On the run from predators, giant schools of fish swim in seemingly choreographed motion – remaining together in a group as they try to out maneuver the enemy. This actually works better to save more little fish hides than everyone swimming away in a different direction. But how do the fish manage to swim together in one large body like that? It’s as if they join together – like how all the individual robots come together to form one big one in the Mighty Morphin’ Power Rangers. Yeah, MMPR!! Right guys?! Guys?

But the fish aren’t joined together and their motions aren’t choreographed. So how do they do it?

The basic mechanism behind fishes’ ability to make these synchronized movements has been understood for some time. Fish have what is called a lateral-line system, extending from the fishes mouth to its tail. Along the lateral line are a series of two types of sensors: one which measures changes in the velocity of the surrounding water, and another which detects changes in pressure. The former are called surface neuromasts and the latter are called canal neuromasts. The surface neuromasts are made of sensors that stick up like a mast on a ship, although they are only the size of a short hair. The canal neuromasts are more like little trenches below the scales, and they detect pressure in the surrounding water through two pores positioned on either side of the neuromast.

These neuromasts allow fish (especially those living in murky waters or dark locations) to determine the motion of their neighbors, the presence of obstacles, and the motion of potential predators or prey. The range of this detection method is limited – at most, the body length of the fish. In murky or dark waters, this still beats the use of vision. It also beats techniques like sonar, used by bats, which would require the fish to send out a signal that would also alert predators, or prey, to the fish’s location.

Fish that dwell in water that is mostly still, like goldfish living in quiet ponds, will have more sensors geared toward changes in velocity, good for detecting water motion or wakes created by swimming fish in the area. Fish living in more tumultuous locations, like trout in raging streams, will have more canals that detect changes in pressure.

At the APS March Meeting, Dr. Leo van Hemmen of the University of Technology Munich (TUM) in Germany, discussed his group’s work to understand how this lateral-line system and the ensuing neuronal information processing connect to fishes brain, and help fish create a three-dimensional map of their surroundings. In collaboration with TUM’s electrical engineers, lead by Dr. Sandra Hirche, his group is currently building a water-going robot that operates using a lateral-line system also constructed by the group. Van Hemmen and his group nicknamed the robot Snooki, although there is no connection to the Jersey Shore star (you were so confused by the title of this post! I’m sorry I dragged you along for so many words). The robot Snooki is fully equipped with sensors and additional hardware modeled after the neuronal system.

Besides potentially developing the lateral-line system for use in another robot, the group is using Snooki (shown right, photo courtesy of Dr. van Hemmen) to study studying how the fish manage to integrate the input from the canals into their mental map of their surroundings. Human brains put together sight, sound, and touch into a cohesive picture of our world. This input is transcribed through some complex neuronal activity, and van Hemmen and his group want to try to understand that process of passing the information from the sensors to the brain, and turning it into an integrated local map. Replicating this process in robots, which sometimes use six cameras, is a challenge. The TUM researchers would like to find a way to integrate six cameras so the input is reduced to what you might get from only two cameras (much more manageable).

Their work could also be used to make more sensitive detectors of this type operating in air. Researchers at the University of Twente in the Netherlands have built sensors similar to Snooki’s surface neuromasts velocity detectors, but theirs were patterned after those found in crickets. These detectors can respond to changes in airflow velocity less than 1 mm/sec, but the ideal is to reduce that by a factor of ten so as to attain optimal response. Ideally, Snooki or her descendents will help with this pursuit.

Friday, April 23, 2010

Spider-Man fever never seems to die. Just Google-news search "spider" and you'll see what I mean. Apparently there's a Spider-Man Broadway musical set to be produced (and Alan Cummings has bailed out - but we should have seen that coming). I live in New York City and I can honestly say that I may never go see a Broadway musical and I will not feel bad about it. Still, I recognize the iconic/ridiculous popularity that something must reach before it is turned into a Broadway musical (see: Toxic Avenger)(did I just invalidate my own point?).

But that's not all. Now it seems you can have Spider Man clean your windows for you. A full grown man or woman who is already performing a very dangerous job will now dress up in a costume fit for a child and perform that same job for the entertainment of the many onlookers who have previously stopped to watch window washers but have felt that it lacks zest (what? exactly.). The company featuring these costumed clean-saders (get it?!!) said that they want to add fun to whatever they do. Although if we think this through, the person who is doing the job (the window washer) is probably not enjoying dangling from a sky scraper and wearing a mask. (Am I crabby today, or does anyone else feel bad for the window washers?)

Lets talk some physics. I had wanted to continue up my post about rope with a discussion about strong materials. The wonderful lecture by James Kakaliosat the APS March Meeting taught me that spider silk is one of the strongest naturally occurring materials in the world. In researching this post I'm just overwhelmed with all the awesome little things I'm finding about spiders and their amazing materials.To illustrate the strengths of spider silk, Kakalios showed a scene from Spider Man 2, in which Spidey stops a speeding train using his webs. Assuming the speed and weight of the train, and how far it had to slow down, and taking a stab at the thickness and number of web strands, Kakalios shows Spidey would, in fact, be able to stop that speeding train, while even steel cables would not. Real spider silk in a quarter inch thick strand can support 6,000 pounds. (See his answer to that and other questions here.)

So why can't we buy spider silk rope in our local hardware store? Or make a clothing from it (which would be lighter and stretchier than Kevlar, although Kevlar is slightly stronger*)? Well, apparently reproducing spider silk is not so easy. This article from Live Science in 2004 calls reproducing spider silk on a larger scale "the holy grail of materials science." A bit of a journalistic overstatement I think, but obviously intended to convey great importance. Because really, the Holy Grail of anything is the Holy Grail. There's really no substitute for eternal life, is there? I am full of distractions today.But really, this whole post is a distraction. There's some physics in here about spider silk and its strength and flexibility, but mostly it's just marveling at spider amazingness. There is seriously so much cool stuff to learn about spiders. Did you know their blood flouresces? (See pic to the right) Did you know the pain from a spider bite may be similar to the pain you experience when you eat hot food? Then there's the super strong nano-structures that exist in their fangs. If these things were the size of tanks they would rule the world. Luckily, it doesn't seem like those super structured claws or the super strong spider silk can transition to the macroscopic world very easily.

Scientists have even taken spiders to space. When building a web, spiders can sense their own weight, which provides a guideline for how thick the silk should be. NASA scientists immediately challenged the spiders by chanting, "Oh yeah? Betcha can't do that in zero gravity!" Living up to their end of the challenge, NASA scientists took common garden spiders (Araneus diadematus) spiders into space, where they were still able to build webs, and over time got better at building them in zero gravity. Their results showed that the web threads were finer in space than on the ground. So the weight sensing mechanism works pretty well.

As for manufactured reproductions of spider silk, there seem to be few if no updates on work that was done five or six years ago. Well, at least not breaking news stories about it. The subject of spiders and there silk, however, remains heavily researched by groups like the Oxford Silk Group, who were featured on some British TV shows to talk about this stuff.

All this spidey awesomeness - is this why people still have Spider-Man fever, years after the third and terrible movie came out? I enjoy a good comic book, but these real life spiders are the ones who have me tangled up in their web.

OK, that was kind of horrible. Let me try that again:

The comics are great, but it's the real life spiders that will bite you.

That one didn't make sense. Here we go:

Comic books will capture our imaginations, but real life spiders will hit us in the face with their steel cable webs of awesomeness any day!

That's the one! Call the Nobel Committee! Happy Weekend!!

*Searching the web to find out of Kevlar is stronger than spider silk will give you mixed results, but more cited sources suggest Kevlar is as strong or slightly stronger than spider silk.

Thursday, April 22, 2010

According to the giant calendar above my desk, today is Earth Day. That calendar is made of paper (and is designed with atrocious colors but that's what you get for $1.99), and come December its corpse will become waste unless I decided to haul it back to my apartment where we have recycling. On Earth Day I feel particularly motivated to do things like reduce, reuse and recycle. I get the same buzz when I buy a new reusable grocery bag or watch a documentary about penguins. But it's just so easy to slack off in my Earth-saving habits for about 300 days out of the year. The rest of the time, it's either out of my mind or secondary to so many other things. Saving the Earth is something I'd like to do, but I also want to make my yoga class this afternoon and that has some more immediate benefits. So I use one more plastic bag; I throw away a container I could have reused; I do not, for one moment, Save the Earth.

And maybe it is so easy for me to forget about Saving the Earth because we call it "Saving the Earth." To save something seems like a choice that only impact the thing we are saving. Like pulling a small child out of a pool, we save the child. The only benefit to ourselves is the new sense of self congratulation. But in the case of the planet - it's dangerous levels of CO2 and overwhelming piles of waste - what "Save the Earth" doesn't address is the fact that we humans are actually the thing that needs saving.

If you do nothing else today, I beg you to listed to this podcast from Point of Inquiry, which features a short spoken essay by Lauren Becker about why the phrase "Save the Earth" has undermined the importance of this task, and does not actually describe the dire situation we are in. Becker's essay is poignant and enlightening and I listen to it whenever I need a reminder that Earth day is not just about trees and polar bears (although those are important too); it is very much about the survival of us humans. Continue listening to hear a really cool interview with Bill Nye about his plans for a new TV show (joy!).

Wednesday, April 21, 2010

Physics really is the study of everything. By which I mean there is no item or process in this whole wide world that some physicist, somewhere, doesn't want to get their hands on and study. Does that make us all physicists? Even if we are biologists or chemists or cosmetologists? Does that make me a physicist if I feel like studying puppies and Cheetos? Maybe it does. All I know is, today some people who call themselves physicists went out and studied the physics (actually, the geometry) of rope.

Scientists in Denmark posted a paper on the arxiv claiming to have boiled down the nature of rope and found a law that governs when and why a rope will or will not unwind when pulled. Rope is made of strands of material, like wire or fabric, that are each individually twisted in one direction, and then twisted or braided together in the opposite direction. The beauty of rope is that materials which are actually quite weak on their own, can be manipulated to be quite strong. As the researchers stated in an article by Science News, it is a testament to the power of geometry.So does that technically make them geometrists? Is "physicist" just a word we give to anyone who studies stuff that other departments don't know how to categorize? I don't know but I do know that these puppies really want these Cheetos. Physics?

Back on track (rope track): The researchers found that in order to guarantee that the rope does not unwind, one must twist the individual strands of material to their maximum. This they call the "zero-twist point." They then measured ropes twisted to this point and found that in a triple stranded rope, the rope is 68% the length of the untwisted material.

I love the Science News article about this in which an outside expert explains that this is a universal law for rope:

Physicist Henrik Flyvbjerg of the Technical University of Denmark, who was not on the research team but is familiar with the work, agrees: The rule of the zero-twist point is universal.

“If there is life on other planets in other solar systems, their rope makers must follow the same rules,” Flyvbjerg says.

Rope from other planets? Oooooooo.

The researchers also showed why you need to feed the individual twisted strands into the rope at a higher angle than the resting rope. To illustrate, watch the braiding machine featured in this video about how climbing ropes are made.

I could probably babble on about the history of rope, which is one of those commonly overlooked and yet totally essential tools in human development. It's one of those objects that seems to have a debated past. Ropes (distinct from chords or strings) may have been used as early as 28000 years ago, and the first rope-making tools were believed to belong to the Egyptians around 4000 BC.

Ropes made from synthetic material appeared in the 1950's, and most rope that you'd buy at the hardware store is synthetic, made from material like nylon, polyester, Kevlar, polypropylene and polyethylene. You can also find rope made from organic material like hemp, linen and cotton.

Claims for the strongest rope in the world come from a few companies. There's Zylon, which claims to be the worlds strongest fiber. Two companies that claim to have the strongest ropes in the world both have fancy sounding physics names. There's the Purple Plasma Rope from Rope Inc. and the Neutron 8 Rope! I cannot find a deciding contest between ropes for the strongest contender. If you know of one, please share.

Tuesday, April 20, 2010

Electricity, appliances, automobiles are going to be more Internet-friendly 10 years from now. The smart grid idea aims to save money, reduce pollution, lower costs, and create new "green" jobs.

Smart grid is a phrase that refers to a number of things at the same time. It refers to the modernization of the electrical grid itself -- the way electricity is transmitted over long distances and then brought to customers. It refers to things in the home, such as appliances that turn themselves off and on at certain hours in order to save energy. And it can refer to the effect electricity will have on other parts of the economy, such as transportation.George W. Arnold, who works at the National Institute of Standards and Technology in Gaithersburg, Md., has the job of coordinating government programs with private efforts to ensure that new technology coming into being will be compatible with existing grid equipment and with the technology of tomorrow.

Arnold spoke this week about the smart grid in the year 2020 at a meeting of the Association for Computing Machinery in Washington. His talk was a sort of "State of the Union" for electricity in the U.S., as it will be ten years from now.

Here is a sampling of what home electricity might look like in the year 2020. Roof shingles made of light-sensitive materials make electricity to help power the home. Twenty percent or even more of electricity sent by the local utility will be from renewable sources, such as wind or solar power. Many homes will be equipped with "net metering," which means that if you generate more electricity than you can use (from solar cells, say), it can be sent out and added to the general grid.

One of the main goals of an automated smart grid for the home is for appliances to know when to operate. For example, with a single small microchip a dishwasher will start up in the middle of the night, when the cost of electricity is much lower than in the late afternoon.

The advent of smart meters will allow utilities to charge different rates for electricity during different times of the day. Because of this, customers will learn to be thriftier with their energy use. At least that's what energy analysts hope.

Many homes send and receive Internet signals over a phone line or a dedicated cable. The smart grid of tomorrow may carry such information over lines now dedicated to power alone.

"Enernet is our name for a system that combines energy and information," Arnold said.

A greener grid is expected to be a major new component of the economy. Arnold cited a recent study which showed that about 270,000 new jobs relating to the smart grid would be generated over the next few years, and that another 170,000 jobs would materialize in the five years after that.

The government will spend more than $3 billion over the next year or two in helping to promote the smart grid. But is this enough? Massoud Amin, a professor at the University of Minnesota and who helped to promote the idea of smart grid more than a decade ago, says that $10 billion per year is probably a better estimate of what is needed.

Another big element of the smart grid is the effort to electrify cars. Car companies are about to introduce plug-in hybrid vehicles, cars which can go up to about 30 - 40 miles with an electric motor, but which can also rely on a gasoline engine. Electric power is much more efficient than gasoline-driven propulsion. That's the incentive for making more cars at least partially electric.

Arnold said that converting two-thirds of the auto fleet to at least plug-in hybrid status would cut oil imports to the U.S. by half and would reduce carbon dioxide emissions by 20 percent. To do this, however, will require upgrades in several parts of the electrical equipment that deliver electricity to homes. Car recharging, like dishwashing, is best done in the middle of the night, when many electrical generators are otherwise idle. But the power needed for the charging can be as great as that needed for the house as a whole. Therefore new wiring might be needed.

Friday, April 16, 2010

Physics is all about riddles. What are we made of? How did we get here? How do you cool down a group of particles to a millionth of a degree above absolute zero when you can only build a refrigerator that gets down to 4 Kelvin? Physicists must find the answers.

If you like riddles and puzzles, physics probably tickles your fancy. There's a great deal of creativity involved in uncovering lines of cause and effect. Here's one puzzle that me and my friends in undergrad would pitch to newbies:

Start with a room. The room has no windows and one door. Inside the room is a lightbulb. Outside the room there are three switches. One of the switches turns on the light. You are allowed to open the door once, but you cannot flip any switches while the door is open. So, you could open the door while one of the switches is flipped on, but you can't flip the switch off or flip on another switch until the door is closed.

How do you find out which switch turns on the light?

There's a hint and more riddles after the jump.Here's one I love.

Surrounded by loved ones, you die a peaceful death and go to the crossroads of the afterlife. You are presented with two roads. One leads to heaven and one leads to hell (or whatever desireable/undesireable locations you want to imagine). You can only take one path and you cannot change your mind or turn back once you have chosen. The paths look the same from where you stand, and you cannot tell which one leads where. To find out, you must ask the advice of The Twins. But beware: one Twin is good and wants you to take the road to heaven. He will only tell the truth. The other Twin is evil, wants you to take the road to hell, and can only tell you a lie. Like the roads, you cannot tell which Twin is which. And to top it all off, you can only ask The Twins one question to try to figure out which path leads to heaven (only one question, not one per Twin). What question do you ask to guarantee you will find the road to heaven?

The hint for riddle number 1 is that finding the answer has to do with heat. The hint for riddle number 2 is, try to figure out what question they will both give the same answer to.

Answers at the bottom.

The first riddle is about manipulating a system. How do we get the information we want out of it when we can't manipulate it however we please. Limitations in our ability to collect information arise all the time. Some people might say that the answer to quesion one is to smash a hole through the wall so you can see which switch turns on the light. And I guess that doesn't violate the rules. But the better solution is to use what resources you have to get the information indirectly. We cannot, for example, pin down an electron and see exactly where it was and when. So we find indirect ways to detect its presence.

The second riddle is more about knowing the right questions to ask. Sometimes that can impact results as much as the answer. Lost fans know this all to well - it's not where are they but when are they? Ugh.

OK - answers at the bottom, and maybe more examples of physics riddles next week. More riddles here. Happy weekend!

Riddle one answer: The door is closed. Turn on one of the switches and wait a few minutes. Turn off the first switch and turn on the second. Open the door right away. If the bulb is on, it's switch number two. If the bulb is off, check to see if it is warm. If it is, it is bulb number one. If it is neither on nor warm, it must be switch number three.

Riddle two answer: Ask either twin which path the other twin would recommend you take. Either way, take the opposite road.

A few weeks ago, as I was backing out of a parking spot at work, I heard a noise. My noise making skills aren’t nearly as developed as those of the Car Talk guys, but it sounded like a cross between a rattle and a “ping ping ping”, although not as high pitched. The last time I ignored a sound in my car, pieces of it fell out as I was driving, so I decided to do a few laps around the parking lot before heading into DC traffic.

Here is what I noticed-Nothing was dragging behind my car-The sound was most pronounced when I was just starting to move, or just coming to a stop-The noise went away when I was stopped completely-The noise went away when I went above 5 mph or so

Any ideas?

I’ll give you a hint…I had my tires rotated a day or two before.

It turns out that the mechanic forgot to tighten one of the nuts on my rear, passenger side tire. The nut had come off and was rolling around inside my tire. (I didn’t figure out the problem until I consulted with a friend later that night. I just turned up the radio and tried to stay over 5mph all the way home.) Luckily it was only one, the rest of the nuts were tight.

Whew! That was an easy fix. But it did get me thinking about a similar “real world” situation that is in every introductory physics book I have ever seen. It starts something like this,

You swing a pail containing a mass m of water in a vertical circle of radius r…

The object of the situation is not to get wet. So, students are usually asked to find the minimum speed with which you should swing the bucket around your head in order to avoid getting wet. Spin it too slowly and the water will fall out of the bucket when the force of gravity is greater than the centripetal force. Spin your wheels to slowly and the nut will rattle/ping its way to the bottom.

It's a rite of passage problem, and kind of an interesting one, at least to me. But then I started thinking about it from ArtieTSMITW’s point of view…that would be an amusing video. This guy got it right, but I imagine this wasn't the first take.

Maybe a loose nut in your tire is a more likely situation than swinging a bucket over your head, but that video sounds boring even to me. It's definitely important to put physics in real world context for people when we can, for reasons like motivating students to learn physics, demonstrating career opportunities for people that can do physics, and encouraging public support ($$) for physics. On the other hand, forcing necessary problem skills into real world situations can sometimes turn out just ridiculous.

Rapping is my hobby. I work in IT. My frist official rap song was in 2000. I've been making music since 1997. I would write poems and raps while at work and while I was bored or inspired.

How and why did you get into rapping?

I had a love of the music and the environment. I just wanted to be able to express myself and express what I had going on inside. Hip hop is a great way to do that. I got some [music] software and listened to a lot of music and hung out with some musical friends and then started to make my own sound.

Where does the name funky49 come from?

I was at work, back in the day, and I overheard my friend talking to a customer. He was talking kind of loud because the person needed a password that had to have so many letters and numbers and he was annoyed that the person on the other line couldn’t make their own password. He said in this exasperated tone, “Ok, your password is funky49!”

That weekend I went home and made a mix tape of all the beats I was working on, and I gave it to my friend and labeled it “The funky49 mixtape.”

It’s just fun. It just sounded interesting. I didn’t want to make a name for myself or think too hard about it. I just wanted it to happen organically. Sometimes you just see how things go and let them happen.

You see this as a type of science outreach. What does it acheive that other types of outreach don't?

I was contacted by Dr. Kilminster to do it, and it was intended to raise awareness about Fermilab and just give people an extra reason to be interested in science and the research that goes on there. The stuff going on at Fermilb is extremely interesting but not always immediately applicable, so sometimes it’s hard to grasp. When you want to get things out there, I’m a big fan of just using putting the spotlight on it in a large number of ways. Hip hop is very accessible to some people. Fermilab does a lot [of outreach], but as far as getting a message out there I thought this would be an interesting way to raise awareness. I hope I’m able to make things interesting while also presenting accurate science.

You’re not a scientist yourself, and you don’t even work for Fermilab but you’ve chosen to do outreach for them. What motivated you to do outreach on your own? Just a general love for science?

Outreach isn’t something that other people do, it’s something anyone can do. I am most definitely a science fan. One of my favorite memories from growing up in south Jersey was going on a field trip to Philadelphia and going to the Franklin Institute, which is kind of like Chicago’s Museum of Science and Industry. They present a lot of science information and real world applications, and I just got to see a lot of interesting, nerdy science things all in one place. I’m enthusiastic about learning and sharing information with people.

Did you know much about Fermilab and particle physics when you started?

I knew only the very basics of particle physics. I had to do some reading but what I found the most helpful was the PBS documentary called "The Atom Smashers".

Do you consider yourself a nerdcore rapper?

I don’t have the self esteem to label myself as nerdcore. There are much, much nerdier rappers and I don’t know if I’m nerdy enough to be on their level. I like hiphop and if I’m nerdcore I will take up that banner and say I’m nerdcore. This track is pretty nerdy but sometimes you need to be told what your place is and I have not been told that I am nerdcore. But I’m a pretty nerdy guy.

Is there a sense of irony in nerdcore?

I don't see any irony in nerdcore. It's people making music that is authentic to them. That is something that nerd rap can offer audiences... performers being themselves and the audience being able to appreciate that and identifying with the artists. If one does imitate a professional rapper, it is to emulate and incorporate their rap style.

What other raps have you done about science?

I released an EP that was inspired by my local Museum of Science and Industry and that was specifically formed to promote the science museum. One track was on the Bodies Exhibit that traveled there; one was on MOSI permanent structures; there was a track that was bent on a wake-up call for sustainability; there was a cover track by a friend of mine called Mad Science and it was a cute track about Tesla and mad science. There was another piece that was more autobigraphical called “Still Nerdy” and that tells the tale of a fat kid with the glasses, and one of the lines is says how I was fat but now my pockets are fat. I’m not that kid anymore but I’m still nerdy. I like that track. It’s an interesting take on where I’ve been and where I am now.

You didn't go the route that alpinekat did (not that you should have) and make your lyrics explanatory. They seem like they are primarily meant to entertain. But you are both rapping about physics labs. Is there competition there?

That’s what’s cool about science, there’s competitive collaboration. There’s competitive collaboration between CERN and Fermilab. They want each other to succeed but they also want themselves to succeed and they will collaborate but there’s also competition. That happens in rap. You don’t want to be the second best rapper on a collaborative track, you want to be the best. There’s interesting parallels I believe.

I did see the LHC rap when it first came out and I’ve watched it a couple times, while creating my rap. I wanted to be parallel but also to have a different take. They’re both factually correct. It’s not cool to mislead people with half truths. I did have Dr. Kilminster (of Fermilab) fact check my rhymes to make sure I wasn’t telling any falsehoods or being misleading. But I also I guess I didn’t want this to be a classroom instructional piece. I wanted to be more School House Rock where I wanted things to be very entertaining but also extremely educational. A little more digestible and palatable.

And there are messages beyond science that I wanted to get across. In the 3rd verse I wanted to talk about US science test scores dropping compared to other countries. I know somebody’s got to come in third and fourth, but it would be nice since we spend so much on education to get more out of it.

What has the response to the video been like?

People like it. There have been some haters on the internet but let the haters hate. One person says they should have got Eminem to do it which I totally agree with. Why didn’t they get Eminem to do it? I tried to contact Kanye West’s management group to do it. They didn’t reply. Rock bands have covered School House Rock; why not have rappers or country artists or rock artists focus on education? Why can’t something be smart and also make you excited about the music?

Do you think this video competes with professional rappers like Kanye?

No. It would be hilarious if [Kanye] were in the video for a second or something. But he’s up in the stratosphere, and I’m down here in the lower depths of the atmosphere with the humans. That’s what’s going on. The video is very low budget. Dan Lamoureux, the director, did all the shooting and editing on his own time. This is the time and talents of hobbyists. And given enough time and talent you can make up for money that goes into a professional video, but honestly you don’t want it too polished because then you lose some authenticity. Who says it has to be highly polished and professional to be of interest to people? There are a lot of videos out there that are passed around that were shot on a camera cell phone. I would much rather watch something that I really enjoy in standard definition than the stupidest TV show in high def. The message trumps the messenger.

Will you release the song on an album?

I will release it on my pro-science collaborative album entitled "Dirty Apes Discover Science". It will be free to download. I don’t want to make money from it. If people want the mp3 now, they can have it now. I was playing with some different software to make the video compatible with ipods. You can actually get ringtones for the song as well. The lyrics are available; the pictures taken at Fermilab are on flickr. And hopefully it will go more viral, like a tree branching out.

Check out the giant jug vortex we made at the Physics Central Headquarters in College park.

We weren't just fooling around - we were on a quest to make a cool timing device for the upcoming Kinetic Sculpture Race in Baltimore.
The organizers have put out a call for a way to count down the time left before racers like the Rocky Horror Picture Shoe and Cycloctopus have run out of time in the infamous mud pit portion of the race.
If you have a better idea, let us know. We need something that will count down about two minutes with reasonable reliability and precision of plus or minus about ten seconds (it's a sculpture race, not Olympic trials). It should be easy to build - the race takes place May 1, so we don't have a lot of time. It should also be Kinetically Kool, which I can't really define, but if you look at some of the pictures of past races you'll probably get the idea.

Our Giant Jug Vortex runs for a minute and 35 seconds in its current form. We're going to adjust the restriction in the neck to slow it down a little, and add food coloring, confetti, rubber duckies, and anything else we can think of to make it more visible and intriguing.

Here's a video of a video (sorry, I seem to missing a codec or something) showing the vortex timer in action with bits o' stuff added for visual effect.

Tuesday, April 13, 2010

The story of Element 117, the latest addition to the periodic table, just discovered by a team of Russian and U.S. scientists.

Five years of preparation, eight months collecting a few drops of precious radioactive material from a nuclear reactor in Tennessee, five trans-Atlantic flights, millions in research dollars and rubles, and six months of nearly 24-hour-a-day bombardment in a Russian particle accelerator had come to this: Element 117.Six times in the last few months, it had flashed in a detector for a few fractions of a second and then disintegrated away, earning a permanent spot on the periodic table.

This new atom was discovered during a six-month long experiment that ended in late February, according to the team of scientists from Tennessee, California, Nevada, and Russia, who are reporting their discovery this week. Before August of last year, element 117 had never before existed on Earth -- and probably never before in the history of the universe.

Though it has yet to be named, element 117 is the latest in a series of super-heavy atoms to be synthesized in the last few years at the Joint Institute for Nuclear Research in Dubna, Russia. For technical reasons, it was by far the most difficult to make, but its discovery promises to be an important stepping-stone to synthesizing even heavier elements. And it may open the door to better understanding of the mysteries of the atomic structure at the extreme end of the material world.

"[Element 117] is the exploration of new territory -- like the exploration of Africa by Livingston," said nuclear physicist Karl-Heinz Schmidt of the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany, who was not involved in the research.

Reached by telephone yesterday at his home near the institute where Element 117 was discovered, one of its discoverers spoke glowingly of the new element.

"This significantly expands the boundaries of the existence of the nuclei, atoms, elements," said nuclear physicist Yuri Oganessian. "In a word, the boundaries of the material world."

WORK BEGAN IN TENNESSEE

Oganessian is the head of the Russian side of the collaboration and ran the experiments in Dubna where element 117 was ultimately discovered, but the work began in Tennessee about five years ago after discussions between Oganessian and his longstanding collaborator Joseph Hamilton, a physicist at Vanderbilt University in Nashville, TN.

At the time, Oganessian and his colleagues had been using a new technique they developed called "hot fusion" to synthesize a number of the super-heavy elements. This technique used a steady and energetic beam of a rare form of calcium to bombard a radioactive target like uranium. Though hard to pull off, the experiments proved successful because occasionally a calcium atom would come just close enough to one of the heavier target atoms to stick, fusing together to form a new, super-heavy atom. From 2000-05, Oganessian and his collaborators from Lawrence Livermore National Laboratory in Livermore, CA, managed to make elements 113, 114, 115, and 116 in this way.

In 2005, Oganessian was hotly pursuing the heaviest atom ever created -- element 118 -- which he would soon succeed in making by bombarding a target of californium atoms, a highly radioactive element named after the U.S. state in which it was discovered.

Even with that goal still on the table, Oganessian and Hamilton were discussing what would be next. It would have to be element 117 -- lighter than 118, but much harder to make. They knew it was going to prove even more difficult, Hamilton said, because what they needed as starting material was another highly radioactive element called Berkelium, which is also named after the place where it was discovered.

Berkelium is a by-product of producing californium, however. Californium was hard enough to obtain. Getting enough californium to get enough berkelium by-product to do their experiments was going to be prohibitively expensive because it would have to be made in a nuclear reactor that had a high concentration of subatomic particles known as neutrons.

The very best nuclear reactor in the world for this purpose is at the Department of Energy’s Oak Ridge National Laboratory in Tennessee. It was built in the 1960s specifically to produce radioactive elements like berkelium. In late 2004, Oganessian wrote a letter to Alex Zucker, the former director of ORNL, proposing the experiment and asking about the feasibility of producing enough berkelium.

"We saw immediately that this was an interesting experiment to both sides and that working together we could accomplish something that was pretty exciting," recalled James Roberto, who was then the deputy director for science and technology at Oak Ridge.

Officials at Oak Ridge suggested that that they might piggyback on other work going on at the laboratory. Oak Ridge occasionally produces californium for a variety of commercial and research applications.

So they waited until 2008, when the next californium campaign was scheduled. That same year, a symposium was held at Vanderbilt to celebrate Hamilton's career, and he invited both Oganessian and Roberto to attend. Over lunch, they made their plans.

THE THIRD TIME'S THE CHARM

They began in the spring of 2008 of by loading 40 grams of the radioactive element curium into target rods and lowering them into the reactor. These were then bombarded with neutrons for 23 days until the nuclear fuel in the reactor was spent. The reactor was shut down, the fuel was replaced, and then it was bombarded for another 23 days. After that fuel was spent, they replaced it again. And again.

The process lasted a total of 250 days, and it took 11 refueling cycles of the Oak Ridge reactor to produce about 22 milligrams of nearly pure berkelium in the end -- just a few drops in the bottom of a test tube, but more than enough to do the experiment. It still had to be cooled for three months and then carefully chemically purified, which took another three months.

In the summer of 2009, they packed the material into five separate lead safety canisters and put them on a commercial flight to Moscow. At that point, they were working against the clock. The half-life of berkelium is 330 days, and in six months, there might not have been enough left to make element 117.

In something of a comedy of errors, the material was flown back-and-forth across the Atlantic Ocean five times because of incomplete or missing paperwork. It was refused entry into Russia twice, and twice it went back on the return flight to New York, before finally clearing customs only on its third trip to Moscow.

Nobody expected the berkelium to rack up so many frequent flier miles, Roberto quipped, but he added that the overall process was really only delayed for a few days.

From Moscow, the berkelium was transported to the Russian Research Institute of Atomic Reactors in Dimitrovgrad, where it was made into a "target" disk and sent on to Oganessian at the Joint Institute for Nuclear Research.

Finally, on July 27 last year, Oganessian and his colleagues placed the disk in the particle accelerator where it was blasted by a highly energetic beam smashing billions of calcium atoms per second against it. Because the beams were so energetic, the berkelium would have quickly vaporized if left still. So the disk was sent spinning at 2,000 revolutions per minute, and the beam was wobbled and wiggled to keep it from falling on one spot for too long.

What the scientists were hoping for was the rarest of rare events -- a precise collision between a calcium atom flying out of the accelerator and a berkelium atom spinning about on the target.

THE PURSUIT OF MAGIC NUMBERS

Collisions like these are well known to science. Physicists have shown for decades that you can synthesize heavier atoms in the laboratory by smashing together two lighter elements. And atoms smash into each other and create heavier atoms throughout the universe in the wake of massive star explosions known as supernovae. Most of the matter on Earth is the result of atoms smashing into other atoms.

The key to these collisions lies in the nucleus, the heavy and compact heart of an atom. Imagine squeezing nearly the entire mass of Yankee Stadium into a speck the size of a flea sitting on home plate. An atom is like this by analogy -- empty space the size of Yankee Stadium surrounding a tiny flea of great mass.

This is true regardless of how heavy an atom is -- heavier atoms are just like fat fleas sitting in the same huge, empty ballpark.

What makes up the mass of the nucleus are two basic particles packed together: positively charged protons and uncharged neutrons. Protons naturally repel each other, but neutrons act like glue holding them together -- sort of like putting tape on two magnets to hold them together head-to-head or tail-to-tail. The more powerful the magnets are, the more they repel each other and the more tape is needed to hold them together. Likewise, the heavier an atom is, the more neutrons it needs to hold its nucleus together.

"The extra neutrons supply that extra glue to hold these protons and neutrons together," said Hamilton.

But at a certain point, even extra neutrons are not enough. Heavier atoms tend to break apart, throwing off a small fragment of their nuclei over time -- a process known as radioactive decay. Every element known to science that is heavier than bismuth is radioactive and throws off mass like this. And in general, the heavier the element, the more quickly it decays.

Decades ago, physicists predicted the existence of a hypothetical island of stability, in which certain super-heavy atoms that had a particular "magic" number of protons and neutrons, would be more stable. Long sought, this island of stability around neutron "magic" number 184 has proven elusive because of the difficulty involved in synthesizing super-heavy elements.

While scientists generally agree that they do exist, there has been some disagreement over exactly what these magic numbers are, said Schmidt. Different theories have predicted different values for them, which is why the experiments in Dubna were so crucial.

"Since the available theories have already exploited all information available from the accessible nuclei, we need [new] experimental information to settle these questions," Schmidt said.

LESS THAN A BILLIONTH

Back in the United States, Roger Henderson at Lawrence Livermore National Laboratory was downloading three or four data files every day from the Dubna experiment, analyzing them on a computer nicknamed Yana and looking for signs of element 117. When all was said and done, there were billions and billions of events or possible collisions to sort through.

What Henderson (who was duplicating the effort of the team in Russia) was looking for was one particular signature -- a radioactive fingerprint of sorts -- that would be the telltale sign they found the elusive atom. If they truly made element 117, it would exist for a brief time -- a few hundredths of a second -- and then decay into a series of lighter atoms as it threw off chunks of mass from its nucleus.

Several weeks after the experiment began they found the first one on Aug. 20. And by the time the experiment ended six weeks ago, they had detected a total of six events indicating the creation and subsequent decay of element 117.

One of these events occurred when Henderson's colleague Mark Stoyer of Lawrence Livermore was visiting the Russian laboratory for a few weeks and on a side trip to Tobolsk, Russia, at a conference honoring the 175th birthday of Dmitri Mendeleev, who made the first periodic table in the 19th century. "How appropriate that we could add a chemical element to the known elements during this time!" reflected Stoyer.

There is always a chance that what they observed was really due to random events or background noise, but according to Stoyer, this was not likely. He calculated that there would be less than a billionth of one percent chance that the signatures they detected were random events.

SUPER-HEAVY CHEMISTRY

So what does finding element 117 mean?

For one thing, it fills the only remaining gap in the periodic table, which is now complete from the first element (hydrogen) all the way through element 118. Element 117 will eventually be given a name by the researchers, though the discovery first has to be officially recognized by the International Union of Pure and Applied Chemistry.

Even before it has an official name, what the discovery provides is evidence for the island of stability, helps physicists better understand nuclear structure in general, and should help theorists narrow the range of predictions on those magic numbers.

"These experiments are a real tour de force," said Yale University physicist Richard Casten, who was not involved with the research, which is described this week in the journal Physical Review Letters (http://physics.aps.org). "It's an important experimental step that helps pin down interactions that constrain the theories."

One of the most important findings involved isotopes that were formed as the element 117 they made decayed. As 117 decayed, it turned into first 115, then 113 and finally 111. All these lighter elements had already been created previously in the laboratory, but what was new this time was that they were made with more neutrons than even before -- making them far more stable and giving them longer lifetimes.

The newly created element 113, in particular, lasted for about 30 seconds before decaying -- about 100 times longer than previous isotopes of the same element created in the same laboratory in Dubna.

"This does verify that as you get closer to this island of stability you have much longer half lives," said Hamilton.

The added time may also be long enough to be able to do see how these super-heavy elements react with other elements, which would allow scientists to garner information about their chemistry -- -- something that has never been done with super heavy atoms above element 112 before. Those experiments are ongoing now.

"The ultimate goal is a really comprehensive theory of nuclei -- starting from the lightest and going to the heaviest," said Casten.

The work also points the way forward for synthesizing even heavier elements, like element 120, but Oganessian said they will have to shut down and modify their facilities first. In order to achieve an even higher atomic number, they cannot rely on the calcium beams any longer and that they will have upgrade to more intense beams of titanium, which is slightly heavier than calcium.

Work towards that goal is set to begin this year, said Oganessian when a reporter asked him yesterday what is next for the laboratory, though he demurred in his response.

"Do not ask after a substantial dinner what we would like to have for supper," he said.

Will Heitman, a 9-year-old student at Bernard Terrace Elementary, discovered at the event he was 490 billion nanometers tall. [I get the point, but does that number seem a little off to anyone else?!]

And I recently heard this illustration in the context of the national debt,The height of a stack of 1,000,000,000,000 (one trillion) one dollar bills measures 67,866 miles. This would reach more than one fourth the way from the earth to the moon.

I remember grumbling about losing points for missing units when I was in Physics I. Even more vividly, I remember grumbling about how my Physics I students would leave off their units when I was a TA.

Sure, we all know units are necessary and that you might run into some *minor* resistance if you were to measure out a marathon course in kilometers instead of miles. Some of the runners might not be prepared for an extra 16 miles…

But where do units come from, and who determines them?This was (partially) the subject of a recent talk by Neil Zimmerman from the National Institute of Standards and Technology (NIST). The talk centered on a NIST experiment to measure whether the charge of an electron (I’m being loose with my language here) inside of a metal is the same as that of a single electron in free space. This, all with the goal of a capacitance standard based on the charge of the electron. There were many subtleties to the talk, for that I will refer you to one of his papers, but I was particularly fascinated by his discussion of the origin of the International System of Units, or more commonly, SI units.

There are seven SI base units: meter (m), kilogram (kg), second (s), ampere (A), kelvin (K), mole (mol), and candela (cd). The other SI units are derived from these seven: acceleration is m/s^2, density is kg/m^3, magnetic field strength is A/m, etc.

Second--the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom. (And, in case you were wondering,it's a cesium atom in its ground state at 0 Kelvin.)Kilogram--A 1901 platinum-iridium cylinder. Okay, those were my words. But seriously it is.

Ampere--that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross section, and placed 1 meter apart in vacuum, would produce between these conductors a force equal to 2 x 10-7 newton per meter of length.

So we move from a lump of platinum-iridium to infinitely long conductors with no cross section. Such is physics.

Kelvin--the fraction 1/273.16 of the thermodynamic temperature of the triple point of water.

Mole--the amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kilogram of carbon 12.

Candela--the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540 x 1012 hertz and that has a radiant intensity in that direction of 1/683 watt per steradian.

Meter--the length of the path traveled by light in vacuum during a time interval of 1/299,792,458 of a second.

Some of these may seem rather obscure, but remember that the system is continually evolving as measurements get more precise. For example, the second was originally defined as 1/86,400 of the mean solar day, but "the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom" is more reliable.

So my point (in case you are wondering), is that the aggravating SI units all physics students are forced to learn has a rich history and a potentially rich future. Who knows what Will and his generation will uncover. Maybe in 20 years we will need a whole new standard for something yet undiscovered. But, as for the moment, I'm delighted to know that I am roughly 1,701,800,000 nanometers tall.Images:Hundred Dollar Bill Wallet, Amazon.A replica of the real kg, NIST.

Let me just first say that we unfortunately live in a time when physics and hip hop do not frequently come together. I could argue that this disconnect is present in all music, and I think we can all agree that this is because music reflects life, and in life physics is not necessarily a part of the basic human experience. In other words, the reasons that musicians do not write about physics are the same as the reasons that physics might not come up in a discussion at most dinner tables. However, science and physics are not totally absent from music, and upon deeper investigation we find that even with this representation in mind, they are particularly underrepresented in the genres of hip hop and rap. I could potentially put together some thesis argument about how this might be related to race issues in our country, but then I would have to also point out that physics is also mostly absent from Polka and Electronica, and we would be in a bit of a sociological mess.

That said, I have absolutely no idea what prompted funky49 to create this video.I think I am in favor of many of the elements in this video. Doing the low-hug-point thing at the sign for one of the Fermilab experiments? Duh, that is awesome! Using a dosimeter as a prop in a rap video? Go for it! Getting scientists to put on hard hats and try their darnedest to look tough, though they end up just looking cute? Oh yes, bring it on. Saying the word "Prairie" the way a rapper might say the name of the neighborhood they grew up in? Hey, yeah, whatever! Shooting your video next to a bison proof fence while bison eat grass behind you? Uuuuuuhhhhh...I don't think I had thought about that one, but sure!

I appreciate the effort, Funky49, I really do. I appreciate that you got your name tag printed on your shirt. I appreciate that you really seem to think of these physicists as awesome people (which they are). You are no alpinekat and this is no LHC rap, but I do appreciate that you are rapping about physics. Physics is cool and rap is cool, so this makes sense, right? It is apparently not the first instance of this, and I am guessing will not be the last.

Whatever the case, Fermilab deserves some time in the spotlight, so I say more power and bison footage to funky49. Some folks might think that the Tevatron has suddenly become obsolete because the LHC beat it's energy record this year, but that is far from the truth. Folks at the Tevatron are still working their little tails off to hunt for new physics, and their work will deeply impact what is done at the LHC. It will take some time to get the infrastructure of the LHC up and running, and even though there is some low hanging fruit (some analyses that will immediately benefit from higher energy collisions) the Tevatron will still be a contender in terms of science output. And while it will eventually be unnecessary to run the Tevatron along side the LHC, and the Tevatron will hand over its crown as leader of the high energy frontier, it seems like a waste to shut down such a magnificent machine completely. So now Fermilab is looking into how the infrastructure there could be part of a larger machine that would instead lead the intensity frontier. While the energy frontier searches for new physics, the intensity frontier searches for very rare and exotic physics.

I highly recommend you check out this very interesting article providing update from the intensity fronteir. It was written by a very gifted young writer, and appears in the newsletter of perhaps the most prestigious society in the world. Only the best for you guys.